Grinding machine



Feb. 12 1 924. 1,483,748

F. c. SANFORD GRINDING MACHINE Filed July 30. 1920 6 Sheets-Sheet lJnwnioz =k MM Feb. 12 1924.

F. C. SANFORD GRINDING MACHINE Filed July 30. 1920 6 Sheets-Sheet 2 d zu n w 14 a u .r w l e .r u m a a u a 1 3 5 m a m .w V N m a Vl/l/ r E mFeb. 1

1,483,748 F. C. SANFORD GRINDING MACHINE Filed July 30. 1920 6Sheets-Sheet 5 Xx HI gnuc 1 x 4'01 franc/Is GSmgflmi Feb. 12 1924.1,483,748

F. c. SANFORD GRINDING MACHINE Filed July 30. 1920 6 Sheets-Sheet 4 Feb.12 1924.

F. C. SANFO IID GRINDING MACHINE 6 Sheets-Sheet 5 Filed July 30.

\azr a 3 I I 5 4. I I

g I I I I I I I I I I I I I I I y l/IIIIIIIII IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII Feb. 12 1924. 1,483,748

F. c. SANFORD GRINDING MACHINE Filed July 30. 1920 6 Sheets-Sheet 6-lllllllH -llllllll I V/////////////AY/////// Patented Feb. 12, 1924.

FRANCIS O. SANFORD, O! BBIDGEPORT, COli'NIE'I-IGUT.

GRINDING MACHINE.

Application filed July 80, 1920. Serial No. 400,150.

fication.

This invention pertains to that class of.

grinding machines known to the trade as centerless grinders, because thebody to be ground is not carried u 11 centers in a chuck or similarholder w ile being operated upon.

The machine is designed for precision work and, more especial] for ginding to true cylindrical form and to predetermined gage, bodies suchas rollers for antifriction hearings and for like uses, requiring great2 accuracy of form and dimensions, and uniformity of product.

The objects sought are to produce a highl efficient machine of the classnoted, w ic shall be simple in construction, adjustment,

' and operation, durable, and of as small first cost, and as lowmaintenance expense, as consistent with the efiiciency required. Theseobjects I attain by the construction illustrated in the accompanyingdrawings, which no show the best embodiment of my invention now known tome, though it is to be understood that variations 0 the structure may bemade within the scope of the invention, and as may be required orsuggested by different conditions of use.

In these drawings:

Figure 1 is a top plan view of the machine, partly broken away;

Fig. 2, a longitudinal vertical sectional view on the line 2-2 of Fig.1, the base of the machine being represented as cut down to bring theworking parts within the available space on the sheet;

Fig. 3, a transverse vertical section on the line 3-3 of Fig. 1, withthe base similarly cut" down;

Figs. 4 and 5, sectional detail views of one form of automatic clutchingand releasing device'for the driving pulley by which the to governingand feeding wheel is normally driven;

Fig. 6, a partial plan view of the machine, partly in section to showthe springs employed to maintain the adjustable governmg and feedingwheel yieldingly in contact 65 with the work;

Fig. 7, a sectional elevation on the line H of Fig. 6, illustrating thework support and the friction device employed to revent vibration,chattering, or lack of uni ormity of movement of the governing andfeeding wheel;

Fig. 8, a vertical section on the line b--b of Fig. 6 (but with theyoke-supporting head compete instead of cut away as in said Fig. 6),illustrating the manner of mounting and adjusting the yoke by which theshaft of the governing and feeding wheel is carried;

Fig. 9, a vertical section on the line 4-4 of Fi 1 to the shaft or arborof the grindwhee which latter is not in section,

Figs. 10, 11 and 12, detail views of one of the sleeves or bearin s inwhich the main or grinding-wheel she t turns;

Fi 13, a front face view of the yoke whic carries the governing-wheelshaft or arbor and its bearings, the arms of the yoke being shown insection;

Fig. 14, a perspective view of the work so so port and guide;

ig. 15, a fragmentary view illustratin the device for dressing andtruing the grind ing and governing wheels;

Fig. 16, a perspective view of the wheeltruing and dressing devicemounted upon the work support and guide;

Fig. 1 a sectional view of the wheel, nut and screw employed to adjustthe verning and feeding wheel toward and rom the grinding wheel; and aFig. 18, a diagrammatic view showing location of the axis about whichthe governing and feeding wheel is" oscillated or adjusted, to give itsaxis the desired obliquity.

Main frame of the machine-1n these drawings, the machine will be seen tocomprise a main frame of hollow or box construction, here shown asconsisting of a base 1 and an up r section 2, the latter having ahorizonta bed or table 3 and a well 4 to receive the water which issupplied to and flows Qii the work and the rinding and the governin andfeeding wheels, which are peripherall y opposed or in tandem relation.The twopart construction of the box-like frame renders easier themolding and casting thereof, and the meeting flanges of the two partswhich are bolted together or otherwise firmly united, add to therigidity of the structure. Rising from the upper section 2 of the frameare two substantial posts or gillow blocks 5, in each of which is mountea sleeve 6 of brass or other suitable alloy or metal, the two formingbearings for a shaft or arbor 7 which carries the grindin wheel 8. Asseen in Figs. 9 and 11, the s eeves 6 are of tapering or conical form,to fit'correspondlng seats in the pillow blocks or in the top sections 9thereof, which are preferably made se arate from the base portions 5 ofsaid illow blocks, and are secured theretoby eavy bolts 10. Thisconstruction facilitates the taper boring of the top sections 9 of theblocks.

The sleeves 6, after being turned to proper taper and externallythreaded at their smaller ends, are Ion itudinally slitted at one sideas shown at 11 igs. 10 and 11), to permit of contraction to compensatefor wear. Such contraction is effected and the sleeves are securelyretained in place, by screwing a nut 12 onto the threaded smaller end ofeach sleeve, the nut bearing against the outer face of top section 9 ofthe pillow block or post 5 which carries the sleeve. To prevent turningof the sleeves in their seats, each is held by a key 13 seated 1partlyin the top section 9 of the illow bloc and partly in the outer face ofthe sleeve, as seen in Figs. 9 and 10.

The shaft or arbor 7 is preferably left of full diameter from the outerend of one sleeve to the outer end of the other, but is slightly reducedbeyond those points, and at the end remote from the grinding wheel isthreaded as shown at 14, to receive a cap nut 15 and jamb-nut 16, saidcap nut serving to cover the nut 12 and by bearing a ainst the sleeve 6and nut 12, preventing ongitudinal movement of the shaft or arbor 7 tothe left as viewed in Fig. 9. At a point between the sleeves 6 there ismounted on the shaft or arbor 7 a belt pulley 17, which is representedas held in place by binding screws 18, for which any other usual pulleyfastening may be substituted.

Gfiudz'ng wheel and mountings. The grinding wheel 8 is carried,centered. and rigidly held in a divided metallic clamp or headcomprising two main annular members 19, 20, formed respectively withcircumferential inturned flanges 21 between which the grinding wheel isclamped. The member 19 is formed with a sleeve 22, bored to make a closefit upon the reduced end of the shaft or arbor 7, on which it is held bya key 23 and also by a pin 24 passing transversely through 1,4aa,14a

the sleeve and said shaft, the purpose of the pin being to recludemovement of the sleeve longitudinal y of the shaft, while the keyeffectively prevents rotation of the sleeve and member 19 independentlyof or relatively to the shaft. The member 20 of the grindingwheelcarrier is provided with a somewhat shorter sleeve 25, of largerdiameter than the sleeve 22 and internally threaded to screw upon theexternal thread of said sleeve 22. By tightly screwing the outer member20 upon the member 19, the flanges 21 of said members 19 and 20 arecaused to firmly grasp and securely hold the annular grinder or wheel 8between them. To prevent accidental separation or loosening of themembers 19 and 20 of the grinding-wheel carrier, a jamb-nut 26 isscrewed upon the sleeve 22 outside or back of the member 20, and turnedfirmlty up against the same. The radial web 27 o the member 19 of thegrinding-wheel carrier abutting against the outer end of sleeve 6 andits nut 12, precludes longitudinal movement of the shaft or arbor 7 tothe right as viewed in Fig. 9.

It will thus be seen that the shaft 7, which in practice is of quitelarge diameter, turns in sleeves or bearin s which may at all times bemade to fit the sl aft snugly and as closely as is consistent withproper turning freedom, but without the possibility of play eitheraxially or radially to the axis. This rigid supporting of thegrinding-wheel arbor is a matter of great importance in a machine ofthis character, and articularly so where the machine is intended forprecision work.

The annular grinding wheel 8 is carefully trued both as to its centraleye and its circumference, the eye being made of a diam eter to fitsnugly the annular rims of the clamping members 19, 20. so that whensaid wheel is clamped by said members it will run true and in perfectbalance. thus avoiding the vibration which might otherwise be producedand which would tend to chattering of the work in its travel through themachine. It will be noted that the grinding wheel, which in practice isadvisably made of materially greater diameter than the governing andfeeding wheel, is not mounted for adjustment, either toward and from thegoverning and feeding wheel, laterally, or otherwise.

Go'vemz'ng' and feeding wheel mm) mount inga-Go-operating andsubstantially in plane with the grinding wheel 8 is a governing andfeeding wheel 28, which is likewise of annular form, and is clampedbetween disks 29 and 30 carried by a spindle or arbor 31, as best seenin Fig. 3. This spindle or arbor is furnished with a collar 32. whichforms an abutment for the disk 30 and itself abuts against one of theboxes or bears 33 in which the opposite ends or jourin na s of saidspindle are carried. The bearings 33 are preferably slittedlongitudinally on one side,the lower side as shown in Fig. 3-andprovided 'with bolts 33 by which they may be slightly contracted toeffect a close fit or tight contact with the journals of spindle 31, orto compensate for wear of spindle or bearings. it being of peculiarimportance in a precision grinder of the centerless type that all lostmotion or play of the spindles or arbors and consequently of thegrinding and the governing and feeding wheels, be avoided or reduced tothe practical minimum.

The disk 30 is advisably keyed upon the s indle 31, to preventindependent rotation t ereof and better to insure the non-rotation ofthe governing and feeding wheel 28 upon or independently of said arboror spindle. The clamping disks 29 and 30 are firmly pressed into andheld in binding engagement with said governing wheel by a heavy nut 34screwed upon the spindle 31. The bearin s 33 for the arbor or spindle 31are forme upon or carried by a yoke 35 of the form best shown in Figs.1, 6 and 13, said yoke comprising a vertical plate 36 of annuar formhaving laterally projecting arms 37 and extensions 38 which may beintegral with the arms 37 or, as shown in Figs. 1 and 6, may be boltedto said arms. This latter construction is in some respects dcci'ncdpreferable. as a matter of convenience in manufacturing and assemblingthe machine. The annular portion 36 of the yoke encircles and snuglyfits a circular boss 39 formed on the upright face of a hollowsupporting head 40, said head being formed upon or rigidly secured to asliding carriage 41 movable upon ways on the table 3 of the main frameof the machine.

The purpose of, thus mounting the yoke 35 is to permit it to be rockedor tipped so as to place the axis of spindle or arbor 31 and its bearingin horizontal plane or in a plane oblique to the'horizon, as may berequired. When it is desired to effect an automatic axial feed ortraverse of the object being ground, the yoke 35 is rocked or tippedmore or less about the axis of the boss 39 to set the axis of spindle orarbor 31 more or less oblique to the horizon, assuming that the centersof the two wheels 8 and 28 are normally in common horizontalplane, aspreterably they will be. To permit such adjustment of the yoke 35 whenrequired and to hold the same rigidly against movement after properadjustment has been effected. the annular plate 36 of said yoke isprovided with curved slots 42 concentric with the axis of the boss 39.and bolts 43 are passed through the slots and into or through openingsin the supporting head 40. the inner ends being provided with nuts 44which being duly tightened. clamp the parts rigidl together.

Work-rest; three-paint support-45 indicates a main work-rest sup orthaving two sections 45' and 45" of like orm and height, made fast to orintegral with a connecting plate or bar 46 and spaced the grinding andthe governing and feeding wheels to stand between them, as seen inFigs. 1. 6 and 14-. Each section 45' and 45 is in the form of a smallstool having in its upper face a slot or groove 47 to receive acylindrical rod or bar 48, which in practice is made of steel andtempered quite hard to resist wear, and is of a diameter to fit somewhatfreely in the groove 47. The bar 48 is clamped and held in said grooveby horizontal set screws 49, seated in tapped holes in the support 45,hearing at their inner ends againstthe bar 48 and serving to press andhold the same firmly in contact with one of the walls of the groove 47.The cylindrical form of the rod 48 permits the same to be made perfectlytrue by turning in a lathe or by grinding, and presents only a linecontact with the work which it supports; hence permits the work to turnwith little friction and by reason of its circular cross section,permits or causes all solid particles of grit or metal to fall away fromthe work, thus preventing the same from becoming scarred or scoredthereby.

In practice, I provide several of the workrcst supports 45 withdifferent heights of stool or upright supporting member, to the end thatthe axis of the object ground or operated upon by the wheels 8 and 28may be always somewhat below the common plane of the axes of saidwheels, or of the axis of wheel 8 and center of wheel 28. The pur-" poseof thus maintaining the axis of the work below the plane of the centersof the wheels at the point of grinding, is to keep such work in a throatwhich decreases slightly in width upwardly from the points of contactwith the wheels. By this arrangement the Work has three points ofcontact,-the lower or supporting contact c, the governing and feedingwheel contact a. and the grinding wheel contact 6. (See Fig. 2). The twopoints of contact 0 and 6 will. if the work, the supporting bar and thegrinding wheel each be truly cylindrical and parallel. be a mere contactline. The contact d. will likewise be a straight line contact if thegoverning and feeding wheel 28 be truly cylindrical and its axis beparallel with the axes of the work, the work-rest, and the grindingwheel. If the axis of the govering and feeding wheel 28 be set obliqueto the horizontal plane of the axes of the work and grinding wheel 8,the surface of the governing and feeding wheel will speedily wearslightly concave, the degree of concavity varying with the obliquity ofthe axis of the arbor or spindle which carries the governing and feedingwheel, but being apart to permit slight and almost imperceptible underany usual or desirable degree of obliquity of the wheel axis. \Vhen thewheel 28 becomes thus concave the bearing will still be along a straightline.

The office of the governing and feeding wheel as its designation wouldsuggest, is to effect and to overn or control the rotation of the work,to support it properly in contact with the periphery of the grindingwheel, and to effect the axial traverse or feeding of the work, thewheel 28 acting upltlin the well-known principle of a skew ro The wheels8 and 28 are rotated in the same direction, that is to say, both rotateclockwise or both anti-clockwise, according as the machine is viewedfrom one or the other side, the larger or grinding wheel moving downwardand the smaller or governing and feeding wheel moving upward where theycontact with the work. Suitable provision is made whereby the rotationof the governing and feeding wheel is made relatively slow and that ofthe grinding wheel is made relatively fast. In practice, the speeds andthe ratio of speed may vary within reasonable limits, depending somewhatupon the nature of the object ground and the amount of material which itis desired to remove in a given time or with a given traverse of thework. I have found for general use with iron and untempered steel, aspeed of about 1000 revolutions per minute for the grinding wheel and38-60 revolutions for the governing and feeding wheel gives satisfactoryresults, with an assumed diameter of twenty inches for the grindingwheel and ten inches for the governing and feeding wheel. In thedrawings the wheels are shown of relative diameters of two to one, thegrinding wheel being the larger, but neither this nor any other specificrelation is essential to the successful operation of the machine. Itherefore contemplate varying the same at will or as found expedient ingrinding different metals, alloys, or other substances and under varyingconditions.

Feeding adjiwvnwnt of governing and feeding wheel-4t is to be noted thatunder the arrangement shown in the drawings and with the grinding andthe governing wheel axes when both are horizontal, lying in the samehorizontal plane, the tipping or rocking of the governing wheel is aboutits central point, that is to say, about a point not only central withreference to the circumference or periphery of the wheel but 1 ingmidway between the breasts or side aces of the wheel, when the wheel isa short section of a cylinder, as illustrated. In other words, the axisof tipping or rocking of the yoke 35 is coincident with a. line radialto the axis of the grinding wheel 8 and lying in a vertical plane whichbisects the workin face or peripher of said wheel, and whic 1 when theaxis 0 the governing and feeding wheel 28 is parallel with that ofgrinding wheel 8, similarly bisects the peripheral working face of saidwheel 28.

Under this arrangement, which is preferred though not essential tosuccessful operation of the machine. a more symmetrical construction,better balancing of parts, and minimum variation in extent of the lineof contact between the governing and feeding wheel and the work, aresecured. An important advantage of this location of oscillation ortipping of the yoke 35 and spindle or arbor 31, is that it involves nochange whatever in the adjustment of the workrest or its support, thatis to say, in the height thereof and consequent location of the workaxis. The best attainable position or elevation of the work axis willunder the arrangement just described, be the same whether the axis ofspindle or arbor 31 be parallel with or more or less oblique to the axisof wheel 8. The ti ping of wheel 28 and its spindle or arbor about suchcentrally located point involves merely a partial rotation of said wheel28 face-wise or breastwise, without any bodily translation or shiftingof the wheel, whereas movement about an axis otherwise located involvessuch bodily shifting of the wheel and consequent change of relation ofthe wheel to the work and its support.

Under this arrangement a horizontal straight line will .pass through theaxis of the annular plate 36 of the yoke 35, through the center of wheel28, and through the center of wheel 8, and relatively slight tipping ortilting of said yoke will give suiticient obliquity to the axis of thegoverning and feeling wheel relatively to those of th work, work-restand grinding wheel, to insure the axial feed or spiral advance of thework incident to the use of the skewed roll. Such adjustment can be madewithout in any manner disturbing the relation of the hearing orcontacting point of the governing or feeding wheel with the work, orwithout necessitating a raising or lowering of the work-rest. A locationof the pivotal axis of the yoke 35 a short distance to one or the otherside of the medial plane of the wheel 8, while deemed undesirable, wouldnevertheless be within the limits of my invention, but the axis ofoscillation should. to insure good results, be kept within the thicknessof the wheel or not be carried beyond the side faces thereof. The morenearly the symmetrical arrangement is maintained, the more satisfactoryis the operation of the machine, and the greater the facility andaccuracy of adjustment, for reasons above pointed out.

Experimentation and practical tests have demonstrated material advantagein adjusting the governing and feedin wheel rather than the grindingwheel. In act, it is found that in order to get rapid and ellicientgrinding, the grinding wheel must have a high sur face speed, whereasthe work should be turned at a relatively slow speed, suflicient only topresent the different faces of the work successively, gradual] anduniformly to the inding wheel. Since rotation of the work is effectedand governed b the governing and feeding wheel, the sur ace speed of thelatter must necessarily be relatively slow, and is in fact so slow as toproduce no a preciable grinding effect, if indeed, there any slip orrelative surface movement between the work and the governing and feedingwheel. Said governing and feeding wheel hence, by reason of its upwardmovement in contact with the surface of the work, rotates the latterabout the work axis, and by reason of the skewed or oblique relation ofthe axis of the governin and feeding wheel relatively to thato the work,causes the work to advance axially with a spiral or screw-like motionacross the face of the grinding wheel, thus resenting the entire surfaceof the work throughout the length thereof, progressively to the grindingface. The axial and the rotary move- Inents ofthe work are thus effectedat a very uniform speed or rate, causing the grinding effect to belikewise uniform and insuring the equal grinding of every portion of thesurface.

So far as I am aware no one has ever heretofore arranged an abrading orgrinding wheel and a governing and feeding wheel in peripheralopposition, with their centers in common plane but with the axis of thegoverning and feeding wheel oblique to such plane, and driven saidwheels both in the same direction, the grinding wheel at a relativelyhigh speed and the governing and feeding wheel at a relatively lowspeed. This special combination and arran ement of grinding andgoverning and ceding wheels gives very satisfactory results, simplifiesthe construction, adjustment, and operation of the machine, and enablesme to attain a recision of form and dimensions unattainab e by any priorgrinding machine or structure of which I have knowledge. bCylinders,however short, may be ground y it.

Briefly restated, in a machine constructed as above described, thework-rest serves solely to support and guide the blank or object ground;the governing and feeding wheel serves to impart rotary motion to theblank or work at any desired surface speed or number of turns perminute, to hold the work up to or against the periphery of the grindingwheel and gage the space between the two wheels, and if the axis of thegoverning wheel be set oblique to that of the grinding wheel, saidgoverning wheel also serves to impart to the work a longitudinal oraxial Adjustment to accommodate work of different diametere.To enableproper adjustment to be made to suit or accommodate work of differentdiameters, I not only rovide separate work-rest supports or stoo s ofdifferent hei hts, but rovlsion is also made for setting t e governingand feeding wheel 28 closer to or further from the grinding wheel 8, andfor positionin the work-suports so as to brin the axis of the bar 48 1nvertical plane with that of the work itself. This I accomplish in themanner illustrated in Figs. 1, 2, 3, 6, 7 and 8, wherein it will be seenthat the bed or table 3 of the main frame of the machine is rovided withlongitudinal dove-tail or un ercut ribs or ways 50, parallel to eachother, and servin to support and guide the slide 41 whic carries theyoke-support 40, yoke 35, arbor 31, and governing and feeding wheel 28as above described. Screwed into the back or inside face of the boss 39or of the upright face or wall of the support 40, are two parallel rods51 which extend through and project beyond the outer end wall of saidsupport 40, as best seen in Fig. 6. Each of these rods 51 is shownencircled b a strong spiral spring 52, preferably woun to tapering orconical form, and havin their forward ends arranged to bear against theinsidefaceofthe u ri ht inner end wall of the support 40, whi e t eouter and larger ends of the springs encircle bosses formed on afollower 53 sliding u on the rods 51 and carried by a heavy ro 54, thereduced and threaded end of which is screwed into the follower plate 53and furnished on its protruding end with a binding or lock nut 55, asshown in Fig. 6.

The rod 54 is externally threaded throu h out the major portion of itslength, an is encircled by a long cylindrical nut 56 flanged at one endand carrying at the opposite end a hand-wheel 57 keyed upon it, thetubular body of the nut being mounted to rotate in the tubular head of apost or standard 58, bolted or otherwise firmly secured to the outer endof the bed or table 3 of the machine. The nut 56 being prevented by theflange at one end and the hand-wheel 57 at the other, from movingendwise, will upon bein turned im art longitudinal motion to the treaded 1'0 54 and consequently to the follower 53, and through thelatter to the su porting head 40 an slide 41, oke 35, arbor 31 and wheel28, when sai rod is moved inward. As shown in Fi 6, the rods 51 areencircled by] tubular s eeves or coverings 59, outside or ack of thefollower 53, and these sleeves are revented from esca ing from the rods51 y nuts 60.

e initial com ression of the springs 52 may be varied as esired byturning the nuts 60, and the compression of the sprin will be such as tohold the governing and liding wheel 28 against the work with suchpressure and firmness as to prevent pla or chattering and to afford thenecessary riction to rotate the work.

The pitch of the screw thread on rod 54 is made relatively slow so thatthe slide 41 and the wheel 28 shall move but sli. htly for a givenamount of rotation of the land-wheel 57, thus insuring delicacy ofadjustment. In practice it is found extremel diilicult to get the lastand very minute adzjlustment necessary to determine to the one-tousandth, fivethousandth, or smaller fraction of an inch, the correctand precise position of the governing and feeding wheel. This it isfound can often be attained more readily and accurately through a sli httapping of the slide or the support 40 than through turning thescrew-rod to right or left, but the effect of the tapping will dependlargely upon the weight of the hammer or other instrument, and thedistance through and speed with which it is moved. To afford and keepalways present and in position for use, a suitable tapping device, Ipivot or hinge, preferably to the support 40, a weighted arm 61,arrangin the pivot and the weight in such relation t at by lifting thearm more or less and releasing it, the weight will fall by gravity andstrike the rear or outer end of said support 40, and give the minutemovement required to complete the inward adjustment. As the weight andthe length of the arm carryin it remain constant, the extent of lifting15 the only variable factor in the use of this device, and a littlepractice will enable the attendant to lift it to about the same distanceand to get the precise amount of impact necessary. This simple expedientis found to be extremely useful in the practical adjustment of themachine, saving much time, and insuring accuracy of adjustment andconsequently of the finished work.

Adjustment of work-rest and guide. The work-rest support 45 is carriedupon and moves with the s ide 41, and is made capable of adjustment uponand relatively to said slide, to the end that the axis of theworksupporting rod or bar 48 may be brought in vertical plane with ordirectly below the axis of the work itself. This is accomplished bymeans of metal clamps 62, com rising flat metal bars each having oneownwardly turned end to bear upon the slide 41, and a tap-bolt 63passing through a hole in the clamping plate and screwing into athreaded hole or seat in the upper face of said slide 41. The free endsof the clamping plates 62 overlie the bottom connecting bar 46 uponwhich the work-rest supports 45 are mounted, pressing and holding saidbar firmly in contact with the top face of slide 41, and holdin itsecurely against movement when the b0 ts 63 are tightened. By slightlybacking said bolts, the bar 46 is freed to permit its adjustment tobring the axis of rod or bar 48 directly below and arallel with that ofthe work, after which t e bolts 63 are tightened and the parts retainedin proper position.

To uide the work in its passage between the wieels 8 and 28, andmaintain it in proper relation to the cylindrical rod or bar 48, thestools 45 and 45 are provided with angle plates 64 the horizontalmembers of which lie upon the tops of said stools, to which they areclamped in proper relation to the work b tap screws passing throughslots 66 in said horizontal flanges and screwing into suitably tappedsockets or seats in the top faces of the stools 45 and 45". The verticalflanges or members of the angle plates rest against opposite sides ofthe work, and being carefully arran ed in parallelism with the axes ofthe grin in wheel and of the work, they serve to gui e the sameaccurately both in passing to and in leaving the wheels 8 and 28.

Device for preventing chatteriny.1t is found in practice that there isoften a tendency of the workto chatter. owing to one or another causewhich it is not always possible to locate. Such chattering tends toproduce flats or flattened faces on the work, and for this and otherreasons is to be avoided or prevented if possible. This desirable resultI attain by means of a suitable friction device acting upon thegoverning and feeding wheel 28, which device is illustrated in Figs. 1,2. 3, 6 and 7, the construction being best seen in the last-mentionedfigure. It comprises two hinged or pivoted arms 67, each having anarcuate face preferably provided with a lining 68 of asbestos, or othersubstance capable of producing a considerable degree of friction and ofwithstanding the heat incident thereto. The lining may be omitted or maybe of wood, metal, or alloy, but in practice asbestos is found to answerbetter than such metals or alloys. The arms 67 are hung or mounted upona common pivot, which may conveniently be a tap-bolt 69 screwed into anarm 38 of the yoke 35. and are arranged raga- 24a to bear on oppositesides of a neck or collar formed upon the disk 30, as seen in Fig. 3.The requisite friction is produced by means of a spring 71 encircling adraw-bolt 72, which passes through the two arms 67 and throu h thespringr 71, and is rovided with an a justin nut 3 and a 10c nut 74 tohold the nut 3 in its adjusted position. By turning down said nut 73more or less, the compression of s ring 71 may be increased to therequisite degree, and said spring acting downward upon the u per arm 67,and upward on the lower arm 6 by reason of the upward pressure of thesprin beneath nut 73, will maintain a constant an uniform friction uponthe neck or collar 70 and completel obviate an chattering of the wheel28. This friction (levies I also find of very marked importance insecuring a high degree of precision in the finished work.

As above indicated, motion is imparted to the grinding wheel 8 through abelt pulley 17 secured u on the shaft 7. Said pulley 1S driven by a elt75 from a countershaft or prime motor provided with a belt wheel of suchsize relative to that of pulley 17 as to give the requisite orappropriate speed to wheel8.

Feeding wheel drive-The governing and feeding wheel 28, for reasons thatwill presently be explained, has a special drive including universalconnections between the pulley shaft 76 and the spindle or arbor 31, asillustrated in Figs. 1 and 3. As shown in these figures, the shaft orarbor 76 turns in bearings 77 carried by a bracket 7 8 bolted orotherwise made fast to the main frame of the machine. The shaft 76 isconnected with spindle or arbor 31 through a common form of universalcoupling or exible connection, here shown as an intermediate short shaft7 9, which may, if necessary, be composed of two telescoping lpartsincapable of independent rotation, sai shaft being provided at itsopposite ends with yokes connected res ectively with corresponding yokessecure to the spindle or arbor 31 and shaft 79, after the manner of thewell-known Hooke or gimbal joint. Any equivalent universal coupling orflexible driving haft may be employed. As the inclination of the axis ofarbor or spindle 31 is not great at any time, it is usually suflicientto allow slight play of the coupling pins of the gimbals in the yokes,as indicated in said Figs. 1 and 3.

By the use of this intermediate flexible connection or universal drive,wheel 28 may be adjusted toward and from wheel 8 and its axis ofrotation be set parallel or oblique to the horizon at will, withoutdisturbing at all the driving relation between said spindle or arbor andthe shaft 76, which maintains a fixed position at all times.

Mounted upon shaft 76 are two belt pulleys 80, 81, the first of whichnormally pulley 80 is locked to shaft 76 for driving or impartin motionto the same, through a locking device of the character illustrated in Fi 4. This it will be/seen, consists of a cylin rical roller 83 locatedin an eccentric cavity 84 in the hub of pulley 80, which cavitycommunicates with the eye of said pulley. The roller 83 is of slightlysmaller diameter than the greatest depth of cavity 84, that is to say,its eatest measurement 0 a line radial to t c axis of shaft 76. r en theroller is in this deepest portion of the cavity, its surface will be outof contact either with shaft 76 or with pulley 80, and hence cannotcouple or connect the two so as to impart motion through one to theother. When, however, said roller passes into a narrower portion of thecavity 84, still maintaining parallelism of its axis with that of shaft76, it will wedge or bind between said shaft and the wall of saidcavity, and firmly lock the pulley and the shaft together so that motionimparted to the pulley .will be transmitted to shaft 76 and through theintermediate connections to the wheel 28. To prevent this locking actiontaking place under both forward and backward rotation,a pin 85 isarranged lengthwise of the cavity 84 so as to arrest or to support theroller 83 when in that portion of the cavity having the greatest de th,or in other words, when in sition w ere it cannot exert its locking eect. The use of the pin is resorted to as a matter of convenience inmanufacture, since it permits the cavity 84 to be cut by a rotarymilling tool in a very simple and expeditlous way. Any equivalent devicefor locking in one direction and releasing in the other, may be emloyed.

s above stated, the rotation of the wheel 28 is quite slow as comparedwith that of wheel 8, a difference in surface speed of course resultingfrom the smaller diameter of wheel 28 as compared with wheel 8. Thisdifference, however, is multiplied many times by employing belt wheelsof suitable relative diameters for driving the belt 82.

It is expedient at times to impart a much higher speed to wheel 28,.andthis necessitates increasing the speed of rotation of shaft 76. It isdesirable that this increased speed be made possible without unshippingthe driving belt 82 or otherwise disturbing the adjustment andarrangement of parts of the machine. It is with this purpose in viewthat the pulley 81 is keyed or otherwise made fast to shaft 76. A belt86 is arranged to run parallel with the base of the machine and isdriven from pulley 7 to pulley 81, the pulley 7' bein formed as acontinuation of the shaft 7. hen 1t is desired to speed up the wheel 28for the purpose of drexing and truing its surface or for other reasons,belt 86 is placed upon pulley 81 and pulle 7" and turns shaft 76 at anincreased spec This causes said shaft to run faster than but in the samedirection as pulley 80, thereby carrying the locking roller 83 into thedeepest portion of seat or cavity 84 and thus disconnecting the pulleyfrom said shaft. The pulley will hence continue to turn at its normalrate, but the shaft 76 turning in the same direction though at a higherspeed, will maintain roller 83 in its non-locking position until belt 86is removed from pulleys 7 and 81, whereupon the shaft 76 beingmomentarily undriven, will be overtaken or overspeeded by the pulley,causing the roller to be carried into the narrower or shallower portionof the cavit '84, and to lock together the pulley an shaft.

Wheel dressing and timing deoice.1n a machine of this character it is imortant to be able at any time to dress an true the working faces of thewheels 8 and 28, which are ordmarily made of abrading material of likequality and texture or fineness, though I do not restrict myself tomaking both wheels of like material, either as to character or texture.I have illustrated in Fi s. 15 and 16 a simple and convenient means oreffecting the dressing or truing of the wheels when required, and thiswithout necessarily removing any part of the machine except theWork-sustaining rod or bar 48.

As indicated in Fig. 14, the outer end of each of the stools 45 and 45is provided with a tapped or threaded hole 87 to receive a tap-bolt 88by which to attach to each of said stools a guiding block 89 having aslight overhanging ledge or shoulder 90 to rest upon the upper face ofthe stool. so that the block shall be held rigidly against any rockingor tipping when t e tap-bolt is turned tightly home. Each guide block 89is formed with a rectangular opening 91 to receive and guide a bar 92,which carries the diamond-holder 93 equipped with a diamond or likedressing point 94, at each end. Cap plates 95 retain the bar 92 inplace. The holder 93 is seated in'an opening extending from front torear face of the bar 92, and is held therein by a set-screw 96. One endof the bar 92 is slotted or forked to receive a hand-Hover 97, the lowerend of which is extended into a slot in the bottom plate 46 of thework-rest support 45, and pivoted upon a bolt or screw 98. (See Fig.16.) Another screw or bolt 99 passing through the arms of the forked endof bar 92 and through a slot 100 in lever 97, affords connection betweenthe bar 92 and lever 97 through which longitudinal recip- 1,4as,14a

rocation may be imparted to said bar 92 upon oscillating lever 97 aboutits pivot or fulcrum 98.

When it is desired to dress or true the wheels 8 and 28, the wheel 28 isreceded, guide blocks 89 are secured in ition upon the stools 45 and 45"with \t 0 bar 92 in place and e uipped with the diamond-holder 93 andiamonds or points 94, and the stools are so adjusted as to cause the bar92 to stand midway between the opposin faces of the wheels and to bringthe diamon s 94 into cutting relation to the res ctive wheels. Thewheels 8 and 28 are then riven, the former at its normal speed and thelatter at its abnormaher trulng speed, in the manner before explained.By traversing the diamonds crosswise of the faces of the wheels, whilethe latter are thus rotating, their surfaces are speedily dressed trueand smooth. and made ready for precision grindll'ater circulation anddeli'vcry.-To prevent undue heatin of the objects ground and of thegrinding and the governing wheels, provision is made for supplying waterthereto. To this end a nozzle 101 is arranged directly over the worksupport and work, as well shown in Fig. 2 and by dotted lines in Fig. 3.A regulating valve 102 is provided, by which the flow of water may becontrolled or cut off at will, and a constant flow of the water so longas needed is caused by means of a pum 103 of any suitable character,shown in Figs. 1 and 3 as a. small rotar pump located near the floor,and secure to the base of the machine below the shaft or arbor 7 of thegrinding wheel 8. A belt 104 passing about a pulley 105 on the shaft 7and about a smaller pulle 106 on the pump shaft, serves to turn theutter at the requisite speed to cause water to be pumped from a tank 107and delivered through the pipe 108 to the nozzle 101. The water flowingfrom the nozzle keeps wheels 8 and 28 and the work between them, wet andcool and flows therefrom into the well 4, whence it drains by an outlet109 and pipe 110 back to the tank 107. In this way the water is causedtocirculate from the tank through the pump 103, pipe 108, nozzle 101,well 4, and pipe 110 back to the tank, continuously so long as the shaft7 is driven.

As more or less grit wears from the wheels 8 and 28, and as articles ofmetal are removed from the odies ground, these are washed bv the waterinto and through the well 4 and thence into the tank 107. To

revent these matters from being carried y the water back to the pump andbeing thereby delivered upon the work and the wheels 8 and 28, the tank;is divided into two sections b a cross partition 111. That section whichreceives the water forms a settling tank flows over the partition intothe second compartment from which it is drawn by the pump, therebyleaving all of the waste mattor removed by the wheels in the settlingportion of the tank.

110015 or cover or the wheels-To prevent injury to those aving occasionto use the machine and also to ard against water being thrown off into t10 surroundin space by the wheels 8 and 28, a hood 112 is hinged to oneend of the machine frame, in position to be swung up over or outward andaway from wheel 8. Its free ed may be arranged to rest upon an suitabesupport of the machine frame. e wheel 28 may be covered by a similarhood, hinged to or carried by the yoke and extending toward the hood ofthe grinding wheel, but no claim is made to this common expedient.

As the journals for the several shafts turn in quite close fittingbearings, it is advisable to provide said bearings with oil cups of thesight feed type, permitting the attendant to note any failure oflubricant delivery or exhaustion of supply.

Operation-The machine being constructed as above described, the blanksor unfinished bodies to be ground are intro duced between the wheelsfrom one side of the machine, guided in their entrance by the angleplates 64 and work-sustaining rod or rest 48. Owing to the obliquity ofthe axis of spindle or arbor 31 of the verning and feeding wheel 28, thework wlll be both r0- tated and axially fed oradvanced as wheel 28 movesupward and wheel 8 moves downward in contact with the opposite side ofsuch work. The blanks may, if desired, be introduced by hand and movedforward sufiiciently far to cause the leading end to be engaged by thewheels 8 and 28, or they may be caused to feed by gravity down a chute,guide or tube, one after another, and to be presented to and between thegrinding and feeding wheels.

Whenever it is desired merely to grind short bodies without advancingthem axially, the may be placed by hand between the grin ing and feedingwheels, the latter being properly adjusted but in such case having itsaxis parallel or in the same horizontal plane with, that of the grindingwheel 8. If for any reason it be desired to feed from the opposite side,the feeding wheel 28 may have its axis canted in a direction reverse tothat normally given it, or contemplated in the foregoing description.

To enable the operator to determine accurately the angular relation 01'degree of obliquity of the axis of the governing and feeding wheel tothat of the grinding wheel, the top of the circular face of supportinghead 40 may be graduated, and a mark or and when it is full the waterline may be made on the matching curved face of the annular plate 36 ofthe yoke 35, so that the ngmber of degrees of deflection ma beaccurately and easlly read.

he foregoing describes that embodiment of the invention which experiencehas thus far indicated as best, and one which gives excellent results inuse, but it is to be understood that variations, modifications, andsubstitutions may be made within the skill and the knowledge ofdesigners and mechanics, without departing'from the limits of myinvention, and that such changes are contemplated and comprehendedwithin my invention in so far s they shall embody the rinciples and modeof o oration above set orth or shall fall within the range of knownuivalents.

The drawin illustrate and this specification is pre icated u on, aconstruction in which the inding w eel and the governing and feedingwheel are each in the form of a short section of a cylinder, and inwhich said wheels, when their axes of rotation are parallel, lie incommon horizontal plane, the wheels bein of like thickness and theirbreasts or side aces in common plane until the axis of the governin andfeedin wheel is timed to secure the show roll f in effect. bviously,while this is the logica and preferred construction and arrangement, theprinciple or mode of operation, and the function or result, would not beat all changed if the axis of the grinding wheel were relatively higheror lower than that of the governing and feeding wheel, or if instead ofbeing in true vertical plane the grinding wheel were in a plane obliqueto the vertical, provided the relation of the several parts one toanother remain as shown and described. In other words it is notessential that the centers of wheels 8 and 28 both fall in a horizontalline or plane radial to the center of wheel 8, but said line may bethrown upward or downward from the horizontal plane to any extentdesired, assuming that a corresponding movement or re-positioning of thegoverning wheel workrest support, and their adjusting and holdingdevices be made, so that except as to bodily shifting of said parts in acircular path around the axis of wheel 8 said parts shall continue tohear an unch relation to each other and to the whee 8. It is hence to beunderstood that the terms horizontal and vertical, used in the foregoingdescription, are predicated upon a specific embodiment of the invention,and the relative positions of parts illustrated in the drawings, andsaid terms are not to be construed as limitations or as in any senserestricting said invention to the placing of the wheel centers in acommon horizontal plane.

Manifestly, the friction device for preventing chattering of thegoverning and feeding wheel may consist 0 a single arm held and pressedagainst the collar or hub by spring or weight, and the device for taping the governing wheel support in ma ing delicate adjustments may be aspring-supported weight or hammer arranged in any convenient way topermit retraction to a definite extent, and consequent iven throw anddefinite impact when re- Feased. Variations of the other details of themachine may similarly be embodied in more or less variant forms, commonto like parts in analogous machines; thus the bearings of the grindingwheel 8 may be carried by a bed or slide adjustable to move saidgrinding wheel toward or from the governmg wheel, as has been done inanalogous machines such as those for sizing metal rods and shafts. Inother words, it is sufficient and generally preferable, to adjust butone of the wheels toward and from the other, and mere reversal orduplication of such means of adjustment would in no manner depart fromthe spirit of my invention.

The term governing and feeding wheel is used here to define a wheelwhich imparts rotary motion to a blank or object, and regulates orcontrols the surface speed thereof. Such wheel is variously designatedin the art as a overning wheel, propeller wheel, regu ating w eel,feeding wheel, and the like.

The term yoke is here used to indicate a support which carries andaffords a bearing for the journals of the arbor or spmdle 31, and is emloyed as a generic term for a structure ful lling this definitionwhether made in the precise form and built up of se arate pieces, ashere illustrated, and w ether having two arms and bearings, one at eachside of the governin wheel, or with a single bearing at one si ethereof. The term bearings as used in the claims with reference to theyoke and the arbor or spindle supported thereby, is intended tocomprehend or include both the two bearings at or near opposite ends ofthe spindle or arbor, and the single bearing construction at or near oneend thereof, and the claims are to be read with this understanding.

So, too, while I have shown and deem it advantageous to provide, athree-point bearing in which the throat or passageway for the workformed b the grinding wheel,

overnin wheel and work-rest, narrows at t e side urthest from thework-rest, this is not essential to effective operation of the machine,and such throat may be higher or lower as desired with reference to aplane passing through and parallel with the axis of the rinding wheeland through the center of tie governing wheel.

N 0 claim is herein made to the water supply and circulating apparatus,or to the deyoke rotatable a vices for dressing or truing the grindingtinuation of appllcation Serial No. 533,067,

heretofore allowed, and contains certain claims taken therefrom, butembraces an-l claims also certain features and details nut disclosed inthe earlier application.

Having thus described my invention what claim is 1. A grinding machinecomprising a grinding wheel carried in bearings; a work support arrangedacross and near the periphery of said wheel; a second wheel peripherallyopposed to the periphery of the grinding wheel, located on the oppos'teside of the work su port and journalcd in a out an axis passing throughthe centers of said wheels, radial to the axis of the grinding wheel,and lying in a plane bisectin the peripheral working face of the tin ingwheel; and means for rotating said wheels at suitable speeds.

2. A grinding machine comprising a grinding wheel carried in bearings; awork-support arranged across and near the periphery of said wheel; asecond wheel peripherially opposed to the periphery of the grindingwheel, located on the opposite side of the work-support and journaled ina yoke rotatable about an axis radial to the axis of the grindin wheel;and means for rotating said whee s at suitable speed and in the samedirection about their respec tive axes.

3. A grinding machine comprising a main supporting frame; a shaftrotatably mounted in bearings thereon; a grinding wheel carried by saidshaft; a slide movable upon the supporting structure toward and from thegrinding wheel; a support carried by said slide; a yoke pivot-allymounted upon said support and provided with bearings; a spindle mountedin said bearings and carrying a governing and feeding wheel inperipheral opposition to the periphery of the grinding wheel; a rest orsupport for the work between the grinding and governing wheels; andmeans for rotating said wheels, substantially as set forth.

4. In a grinding machine, the combination of a supporting structure; ashaft or arbor journa ed in bearings thereon; a grinding wheel carriedby said shaft; a slide carried u on said supporting structure and movale toward and from the grinding wheel; a support carried by said slide;a yoke pivotally mounted upon said support and capable of oscillationabout an axis radial to that of the grinding wheel and lying in a planewhich bisects the periphera working face of said Wheel; a spindlejournaled to rotate in bearings carried by the arms of said yoke; agoverning and feeding wheel carried by said spindle and having itseripheral face opposed to the peripheral ace of the grinding wheel; awork rest or support between the grinding and governing wheels; andmeans for rotating said wheels in like direction about their axes and atsuitable speeds.

5. A grinding machine comprising a main frame; a grinding wheel carrieby a shaft rotatable in hearings on said frame; a governing and feedingwheel having its periphery opposed to the periphery o the grindin wheel;a spindle 0r arbor carrysai governing and feeding wheel; a yo e in whichthe spindle is journaled; a

support carried by the main frame and upon which said yoke is pivotallymounted; a work-rest intermediate the peripheries of said grinding andgoverning wheels; a support for said work-rest; means for moving one ofsaid wheels toward and from the other; and means for im tion to saidwheels in t e same direction about their axes and at suitable relativespeeds.

6. A grinding machine comprising a supporting structure provided withbearings; a shaft or arbor journaled in said bearings; a inding wheelcarried by said shaft or at r; a governing and feeding wheel; a spindlefor said wheel]; a yoke in which said spindle is journaled, said yokebeing capable of oscillation in a plane parallel with that of the axisof the grinding wheel, whereby the axis of the governing and feedingwheel may at will be set parallel with or oblique to that of thegrinding wheel; means for rotating'said wheels at desired speeds and inthe same direction; and a work sup ort located between the wheels andexten ing transversely of their peripheral working faces. a

7. A grinding machine comprising a supportingl structure provided withbearings; a s aft or arbor journaled in said bearings; a grinding wheelcarried by said shaft or arbor; a governing and feeding wheel; a spindlefor said governing and feeding wheel, having its axis at a slightinclination to that of the grindin wheel shaft or arbor but in a planeparal el with that of said shaft or arbor, said wheels beingperipherally opposed or in tandem relation; means for rotating saidwheels as desired speeds and in the same direction' about theirrespective axes; and a work-support located between the wheels andextending transversely of their peripheral working faces, one of saidwheels belng adjustable toward and from the other.

8. A grinding machine comprising a supporting structure provided withbearings; a shaft or arbor journaled in said bearings; a grinding wheelcarried by said shaft or arbor; a governing and feeding arting rotarymo-\ posing wheel peripherally o posed or in tandem relation to the grining wheel; a spindle for said wheel; hearings in which said spindle is'journaled; means for rotating said wheels at desired s eds and in thesame direction about their respective axes; a work-su port locatedbetween the wheels and exten ing transversely of their peripheralworking faces; and means for ad'usting one of said wheels toward and tomthe other.

9. In a grinding machine, the combination of a main sup orting frame; ashaft or arbor journaled 1n bearings thereon; a grinding wheel carriedby said shaft or arbor and having a peripheral grinding face; a slidemounted upon the main frame and movable toward and from the grindingwheel; a work-governing and feeding wheel journaled in bearingscarriedby said slide and having its eripheral face in oprelation to t eperiphery' of the "grindlng wheel; and a work support intermediate saidwheels, mounted upon and movable with said slide, and also adjustableupon and relatively to said slide; whereby the work support may beplaced with its axis parallel with that of the grinding wheel and midwaybetween the opposed working faces of the two wheels under alladjustments of the slide.

10. In a grinding machine the combination of a main exporting frame; ashaft or arbor journal in bearings thereon; a grinding wheel carried bysaid shaft or arbor and having a peripheral rinding face; a carriersupported by the main frame and movable toward and from the grindingwheel; a work-governing and feeding wheel 'ourn led in hearings on saidcarrier and aving its peripheral face opposed to that of the grin ingwheel; and a work-support intermediate said wheels, mounted upon andmovable with said carrier.

11. A grinding machine comprising a main frame; a shaft journaled inbearings in said frame; a grinding wheel carried by said shaft; a slidemovable toward and from the inding wheel; a governingand feedin w eelcarried by said slide; means for a vancing and receding the slide andoverning wheel; and a device carried by t e slide and serving to give alight but regulated impact thereto, to effect a slight movement oradjustment thereof.

12. A grinding machine comprisin a main supporting frame; a grindlngwheel mounted to rotate thereon; a slide movable toward and from thegrinding wheel; a work support carried by said slide; a governin andfeeding wheel also carried by the 8 de; and an undpact device carried bythe slide and adapte to impart a light but controllable impact to theslide to effect minute adjustment thereof.

13. A indin machine compri a main fra i e; a grinding wheel carr i g inbearin thereon; a governing and feeding wheel iaving its perl hery(:pposedto that of the grinding whee a sli e movable toward and from thegrindin wheel; a tilting support carried by said s ids and havinghearings in which the governing and feeding wheel is carried; and meansfor rotating said wheels in the same direction and at relativelydifferent speeds.

14. A grinding machine comprising a main frame; a horizontal shaftsupported in bearings thereon; a grinding wheel carried by said shaft; agoverning and feeding wheel arran d with its periphery in opposition tot at of the grindlng wheel; a spindle for said governing and feedingwheel; a tilting support having hearings in which said s indle issupported; an intermediate wor support; and means for securing thetilting support at any desired degree of obliquity to the horizon;whereby the governing and feeding wheel is caused to impart rotation toan object lying upon the work support, and to advance the same axiallyat a s eed de ndent upon the relative obll uity o the axis of thegovernin and feeding wheel to that of the grinding wheel, work support,and work.

15. In a grinding machine, the combination of a su porting frame; agrinding wheel carried y a shaft journaled in bearings thereon; aioverning and feedin wheel arranged wit its periphery opposed to that ofthe rinding wheel; a spindle or arbor for said governing and feedingwheel; a tilting support hav'n bearings in which said spindle isjournafed; and a work support between said Wheels; said tilting spindlesupport being adjustable at will to position the axis of the governingand fee ing wheel parallel with that of the grinding wheel, the work andthe work support, or oblique thereto, as desired.

16. In a grinding machine, the combination with a grinding wheel havinga shaft journaled in bearings; a governing and feeding wheelperipherally opposed to the periphery of the grinding wheel, and havinga spindle mounted 1n bearing:a in a tilting support; a work supporttween said wheels; and means for rotating said wheels in the samedirection and at proper speeds.

17. A grindin machine comprising a main frame; a s aft journaled inbearm thereon; a grinding wheel carried by said shaft; a spindlejournaled in bearings in a plane parallel to that of the grinding wheelaxis; a governing and feeding whee carried by the spindle and am d withits periphery in opposition to that-of the grinding wheel; a tiltingsupport for said spindle movable about an axis lying between the sideWalls or faces of the governing and feeding wheel; and means forsecuring the tilting frame at any desired angular adjustment.

18. In a inding1 machine of the character descri d, an in combinationwith a (grind ng wheel and with a governing an feedmg wheel peripherallyopposed one to the other; an intermediate work support comprising a pairof stools connected and spaced apart by a bar, said stools beingrecessed on their upper faces to receive a work rest; a rod or barseated at its ends in the recesses of the stools and constituting a workrest and means for clamping the ends of the bar in said s.

19. In a finding machine of the character descri d, comprising a grindinwheel and a governin and feeding wheel arran d in eriphera opposition; aslide provi ed wit hearings in which the verning and feeding wheel isjournal a work support mounted upon and movable with the slide andcarrying a work rest extendinghbetween and across the working faces of te opposed wheels; and means for releasably securing the work support tothe slide; whereby the work rest when adjusted is maintained in properrelation to the governing and feeding wheel durin recession of theslide, and may be at once grought back to proper relation to thegrinding wheel when the slide is returned to working position with thework lying upon said rest 20. In a grindingmachine comprising a mainframe and a slide movable thereon; a grinding wheel journaled in themain frame; a governing wheel journaled in bearings carried by theslide; and a work rest releasably secured to and adjustable upon theslide, and movable with the slide toward and from the grinding wheel.

21. In combination with the main supporting frame of a grinding machine,a grinding wheel journaled therein; a slide movable toward and from theindin wheel; a. raised support carried said slide' a governing andfeeding whee journaled in a yoke carried by said support; rods rigidlysecured to and projecting from said sup ort; coiled springs encirclingsaid rods an bearing at one end against the support; a cross headsliding upon said to s and bearing against the slprm retaining devicesapp ied to sai re s and serving to retain and to adjust the cross headupon said rods; a screw-threaded rod rigidly attached to the cross headand held against rotation; a post mounted upon the main frame and havingswiveled in it a nut screwed upon the threaded rod, and provided withturning means' whereby the governing and feeding whee may be adjustedtoward and from the grinding wheel and yieldingly held in contact withthe work between said wheels.

22. In a. grinding machine of the character described, a grindin wheel;an opposed governing and fee ing wheel; and a friction device acting un, and serving to steady the rotation o the governing and feeding wheel,and to prevent chattering in action.

23. In combination with a grindin wheel and an opposed governing and feeing wheel: a yielding friction device actin upon the governing wheel orits arbor, an serving to prevent vibration or chattering thereof.

24. In a grinding machine, in combination with a grinding wheel and agoverning and feeding wheel. a friction device comprising two pivotedjaws cla ing a collar of the governing wheel; a ho t passing from one tothe other of said jaws; a spring encircling said rod and bearing at oneend against the outer face of one of the jaws; and means for varying thecompression of said spring.

25. A grinding machine comprising a sup rting frame; a grinding wheelhaving a s aft journaled in bearings thereon; a slide movable upon theframe toward and from the grinding wheel and provided with a raisedsupport; a yoke pivotally mounted upon said support and capable ofoscillation about an axis radial to the axis of rotation of the grindingwheel; a governing and feeding wheel having its spindle journaled inhearings in said yoke; a driving shaft; and a shaft intermediate thedriving shaft and the spindle and connected with each by universalcouplings; whereby motion may be imparted to the spindle and adjustmentof the spindle toward and from the grinding wheel and about the pivotaxis of the yoke is permitted.

26. In a grinding machine. the combination of a grinding wheel and agoverning and feeding wheel peripherally opposed; a slide by which thegoverning and feeding wheel is carried; a work support comprising stoolsconnected by a bar; clamps secured to the slide and bearing upon saidbar, and serving to hold the stools in proper position between the twowheels; and a work rest carried by said stools.

27 In combination with the grindin and feeding wheels of a centerlesgrin er, a work support located between said wheels and comprising twoseparated stools having grooved upper faces; a cylindrical rod lying insaid grooves and forming a work rest or hearing; and means forreleasably securing said rod against rotation.

28. A centerless grinder comprising a grinding wheel and a feeding wheelperipherally opposed one to the otheran a work support intermediate thesaid wheels and rallel with the axis of the Bufi'inding whee said worksupport being ciently below the horizontal plane of the wheel centers tocause the work axis to be likewise below said centers; whereb work lyingupon said support will be co ed in a space decreasin in width from thework support upwar and thus prevented from rising from said support.

29. In a centerless grinder, the combination of a supporting frame; ahorizontal shaft journaled to rotate in said frame; a. grinding wheelcarried by said shaft; a spindle having its axis in a vertical laneparallel to that of the grindin wheefaxis; bearlngs in which the journ sof said spindle are mounted; a governing and feeding wheel carried bysaid spindle and peripherally opposed to the periphery of the grindwheel; a work sfiggport intermediate s i d wheels and loca suflicientlybelow the horizontal plane of the wheel centers to cause the axis ofwork resting on said support to be below the plane of'contact of saidwork with the grinding and feedin wheels, and consequently below theplane 0 nearest approach of said wheels; and means for rotating saidwheels in the same direction about their respective axes and atappropnate relative s 30. In a grin machine, the combination of agrinding wheel and a governing and feeding wheel mounted to rotate inperipheral opposition to each other' means for rotating said wheels inone and t e same direction about their respective axes; a work-restextending between the proximate peripheral faces of said wheelstransversel of said faces; and supports for opposite an s of saidwork-rest, located wholly outside of the side faces of said wheels andbeyond the area.

31. A ro grinding machine comprising a supporting structure; a grinwheel journaled thereon; a carriage supported for movement toward andfrom the 'phe of said wheel; a governing or ating v v heel journaled onthe carriage; and a workholder also mounted on the carriage to move withthe governing or regulatin wheel and arranged to support the work tweenthe wheels.

32. A roll grinding machine comprising a supporting structure; a grinwhe journaled thereon; a carriage supported for movement toward and fromthe riphe of sa1d wheel; a governing or regu sting viz heel carried bysaid carriage, and tilted from the plane of rotation of the grindingwheel for effecting a feeding of the work, said wheels being positivelydriven at different speeds and having their peripheries op to oneanother; and means for supporting the work between the wheels.

83. A roll grinding machine comprising a pair of angularly relatedwheels having their peripheries op osed to one another; a stat-ionaround ro part extending between the perip eries of the wheels but out ofcontact therewith and means for adjustably holdin the rod part inposition.

34. roll grinding machine comprising a supporting structure; a grindingwheel journa ed thereon; a carriage supported for movement toward andfrom the peri hery of the wheel; a governing or re gu ating wheelsupported on the carriage in tilted relation to the grindin wheel; aworkholder also mounted on t e carriage to move with the regulatingwheel and to support the work between the co-acting peripheries of theWheels; and means for yieldably advancing the carriage toward thegrinding wheel.

35. A roller grinding machine comprising a grinding wheel; a governingor regulating wheel a slide member carr 1n the latter; a guiding su porttraverse 1e y the slide member; an work-supportin means carried on theslide member in a vance of the regulating wheel, and adjustable thereon.

36. A roller grinding machine comprising a grinding wheel; a governingor regulating wheel' a slide member cart 11 the latter; a guidingsupport traverse la y the slide member; spaced posts or stools on theforward end of the slide member, one on each side of the wheels; awork-su porting member between the wheels; and c am in means carried bythe posts or stools or olding the work-supporting member.

37. A grinding machine comprising a inding wheel; a shaft for said wheeland earings for said shaft; a governing or regulating wheel; a shaft forsaid wheel and bearings for said shaft; means for imparting rotation tothe respective shafts and wheels in the same direction about their axesand at appropriate speeds; and a work-rest intermediate the opposedperipheries of said wheels, the governing wheel having its shaft somounted as to permit its axis to be placed in oblique relation to thegrinding wheel and to the bearing face of the work-rest, whereby1,4aa,14a

the grinding overnin wheel is caused to rotate and ongitudmally feed thework, and

the work-rest is caused to maintain the work in proper relation to thegrinding and govermng wheels.

38. A grinding machine comprising a gzinding wheel; a shaft for saidwheel and arings for said shaft; a governin or regulating wheel; a shaftfor said w eel and bearings for said shaft; means for impartmg rotationto the respective shafts and wheels in the same direction about theiraxes and at a propriate speeds; and a work-rest interme late the opposedperi heries of said wheels, the governing wheel shaft being mounted fortipping about an axis radial to the true center of the grinding Wheel.

39. A grinding machine comprising a grinding wheel; a shaft for saidwheel and bearings for said shaft; a governing or regulating wheel; ashaft for said wheel and bearings for said shaft; means for impartingrotation to the respective shafts and wheels in the same direction abouttheir axes and at appropriate speeds; and a work-rest intermediate theopposed peripheries of said wheels, the governing wheel shaft beingmounted for tipping about an axis radial to the axis of the grindingwheel, and lying between the side faces of said grinding wheel.

40. A grinding machine comprising a grinding wheel; a shaft for saidwheel and bearings for said shaft; a governing or regulating wheel; ashaft for said wheel and bearings for said shaft; means for impartingrotation to the respective shafts and wheels in the same direction abouttheir axes and at appropriate speeds; and a work-rest intermediate theopposed peri heries of said wheels, the governing whee shaft beingmounted for tipping about an axis radial to the axes of the two wheelshafts and 1 ing in a plane midway between the side aces of said wheels.

In testimony whereof I have name to this s ecification.

FRANCIS C. SANFORD.

signed my

